#!/usr/bin/python
# -*- coding: utf-8 -*-

# (c) 2012, Flowroute LLC
# Written by Matthew Williams <matthew@flowroute.com>
# Based on yum module written by Seth Vidal <skvidal at fedoraproject.org>
#
# This module is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This software is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this software.  If not, see <http://www.gnu.org/licenses/>.
#

DOCUMENTATION = '''
---
module: apt
short_description: Manages apt-packages
description:
  - Manages I(apt) packages (such as for Debian/Ubuntu).
version_added: "0.0.2"
options:
  pkg:
    description:
      - A package name or package specifier with version, like C(foo) or C(foo=1.0). Shell like wildcards (fnmatch) like apt* are also supported.
    required: false
    default: null
  state:
    description:
      - Indicates the desired package state
    required: false
    default: present
    choices: [ "latest", "absent", "present" ]
  update_cache:
    description:
      - Run the equivalent of C(apt-get update) before the operation. Can be run as part of the package installation or as a separate step
    required: false
    default: no
    choices: [ "yes", "no" ]
  cache_valid_time:
    description:
      - If C(update_cache) is specified and the last run is less or equal than I(cache_valid_time) seconds ago, the C(update_cache) gets skipped.
    required: false
    default: no
  purge:
    description:
     - Will force purging of configuration files if the module state is set to I(absent).
    required: false
    default: no
    choices: [ "yes", "no" ]
  default_release:
    description:
      - Corresponds to the C(-t) option for I(apt) and sets pin priorities
    required: false
    default: null
  install_recommends:
    description:
      - Corresponds to the C(--no-install-recommends) option for I(apt), default behavior works as apt's default behavior, C(no) does not install recommended packages. Suggested packages are never installed.
    required: false
    default: yes
    choices: [ "yes", "no" ]
  force:
    description:
      - If C(yes), force installs/removes.
    required: false
    default: "no"
    choices: [ "yes", "no" ]
  upgrade:
    description:
      - 'If yes or safe, performs an aptitude safe-upgrade.'
      - 'If full, performs an aptitude full-upgrade.'
      - 'If dist, performs an apt-get dist-upgrade.'
      - 'Note: This does not upgrade a specific package, use state=latest for that.'
    version_added: "1.1"
    required: false
    default: "yes"
    choices: [ "yes", "safe", "full", "dist"]
requirements: [ python-apt, aptitude ]
author: Matthew Williams
notes:
   - Three of the upgrade modes (C(full), C(safe) and its alias C(yes)) require C(aptitude), otherwise
     C(apt-get) suffices.
'''

EXAMPLES = '''
# Update repositories cache and install "foo" package
- apt: pkg=foo update_cache=yes

# Remove "foo" package
- apt: pkg=foo state=absent

# Install the package "foo"
- apt: pkg=foo state=present

# Install the version '1.00' of package "foo"
- apt: pkg=foo=1.00 state=present

# Update the repository cache and update package "nginx" to latest version using default release squeeze-backport
- apt: pkg=nginx state=latest default_release=squeeze-backports update_cache=yes

# Install latest version of "openjdk-6-jdk" ignoring "install-reccomends"
- apt: pkg=openjdk-6-jdk state=latest install_recommends=no

# Update all packages to the latest version
- apt: upgrade=dist

# Run the equivalent of "apt-get update" as a separate step
- apt: update_cache=yes

# Only run "update_cache=yes" if the last one is more than more than 3600 seconds ago
- apt: update_cache=yes cache_valid_time=3600
'''


import traceback
# added to stave off future warnings about apt api
import warnings
warnings.filterwarnings('ignore', "apt API not stable yet", FutureWarning)

import os
import datetime
import fnmatch

# APT related constants
APT_ENVVARS = "DEBIAN_FRONTEND=noninteractive DEBIAN_PRIORITY=critical"
DPKG_OPTIONS = '-o "Dpkg::Options::=--force-confdef" -o "Dpkg::Options::=--force-confold"'
APT_GET_ZERO = "0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded."
APTITUDE_ZERO = "0 packages upgraded, 0 newly installed, 0 to remove and 0 not upgraded."
APT_LISTS_PATH = "/var/lib/apt/lists"
APT_UPDATE_SUCCESS_STAMP_PATH = "/var/lib/apt/periodic/update-success-stamp"

HAS_PYTHON_APT = True
try:
    import apt
    import apt_pkg
except:
    HAS_PYTHON_APT = False

def package_split(pkgspec):
    parts = pkgspec.split('=')
    if len(parts) > 1:
        return parts[0], parts[1]
    else:
        return parts[0], None

def package_status(m, pkgname, version, cache, state):
    try:
        # get the package from the cache, as well as the
        # the low-level apt_pkg.Package object which contains
        # state fields not directly acccesible from the
        # higher-level apt.package.Package object.
        pkg = cache[pkgname]
        ll_pkg = cache._cache[pkgname] # the low-level package object
    except KeyError:
        if state == 'install':
            m.fail_json(msg="No package matching '%s' is available" % pkgname)
        else:
            return False, False, False
    try:
        has_files = len(pkg.installed_files) > 0
    except AttributeError:
        has_files = False  # older python-apt cannot be used to determine non-purged

    if version:
        try :
            return ll_pkg.current_state == apt_pkg.CURSTATE_INSTALLED and \
                   fnmatch.fnmatch(pkg.installed.version, version), False, has_files
        except AttributeError:
            #assume older version of python-apt is installed
            return ll_pkg.current_state == apt_pkg.CURSTATE_INSTALLED and \
                   fnmatch.fnmatch(pkg.installedVersion, version), False, has_files
    else:
        try :
            return ll_pkg.current_state == apt_pkg.CURSTATE_INSTALLED, pkg.is_upgradable, has_files
        except AttributeError:
            #assume older version of python-apt is installed
            return ll_pkg.current_state == apt_pkg.CURSTATE_INSTALLED, pkg.isUpgradable, has_files

def expand_pkgspec_from_fnmatches(m, pkgspec, cache):
    new_pkgspec = []
    for pkgname_or_fnmatch_pattern in pkgspec:
        # note that any of these chars is not allowed in a (debian) pkgname
        if [c for c in pkgname_or_fnmatch_pattern if c in "*?[]!"]:
            if "=" in pkgname_or_fnmatch_pattern:
                m.fail_json(msg="pkgname wildcard and version can not be mixed")
            # handle multiarch pkgnames, the idea is that "apt*" should 
            # only select native packages. But "apt*:i386" should still work
            if not ":" in pkgname_or_fnmatch_pattern:
                matches = fnmatch.filter(
                    [pkg.name for pkg in cache
                     if not ":" in pkg.name], pkgname_or_fnmatch_pattern)
            else:
                matches = fnmatch.filter(
                    [pkg.name for pkg in cache], pkgname_or_fnmatch_pattern)

            if len(matches) == 0:
                m.fail_json(msg="No package(s) matching '%s' available" % str(pkgname_or_fnmatch_pattern))
            else:
                new_pkgspec.extend(matches)
        else:
            new_pkgspec.append(pkgname_or_fnmatch_pattern)
    return new_pkgspec

def install(m, pkgspec, cache, upgrade=False, default_release=None, install_recommends=True, force=False):
    packages = ""
    pkgspec = expand_pkgspec_from_fnmatches(m, pkgspec, cache)
    for package in pkgspec:
        name, version = package_split(package)
        installed, upgradable, has_files = package_status(m, name, version, cache, state='install')
        if not installed or (upgrade and upgradable):
            packages += "'%s' " % package

    if len(packages) != 0:
        if force:
            force_yes = '--force-yes'
        else:
            force_yes = ''

        if m.check_mode:
            check_arg = '--simulate'
        else:
            check_arg = ''

        cmd = "%s %s -y %s %s %s install %s" % (APT_ENVVARS, APT_GET_CMD, DPKG_OPTIONS, force_yes, check_arg, packages)

        if default_release:
            cmd += " -t '%s'" % (default_release,)
        if not install_recommends:
            cmd += " --no-install-recommends"

        rc, out, err = m.run_command(cmd)
        if rc:
            m.fail_json(msg="'apt-get install %s' failed: %s" % (packages, err))
        else:
            m.exit_json(changed=True)
    else:
        m.exit_json(changed=False)

def remove(m, pkgspec, cache, purge=False):
    packages = ""
    for package in pkgspec:
        name, version = package_split(package)
        installed, upgradable, has_files = package_status(m, name, version, cache, state='remove')
        if installed or (has_files and purge):
            packages += "'%s' " % package

    if len(packages) == 0:
        m.exit_json(changed=False)
    else:
        if purge:
            purge = '--purge'
        else:
            purge = ''
        cmd = "%s %s -q -y %s %s remove %s" % (APT_ENVVARS, APT_GET_CMD, DPKG_OPTIONS, purge, packages)

        if m.check_mode:
            m.exit_json(changed=True)

        rc, out, err = m.run_command(cmd)
        if rc:
            m.fail_json(msg="'apt-get remove %s' failed: %s" % (packages, err))
        m.exit_json(changed=True)

def upgrade(m, mode="yes", force=False):
    if m.check_mode:
        check_arg = '--simulate'
    else:
        check_arg = ''

    apt_cmd = None
    if mode == "dist":
        # apt-get dist-upgrade
        apt_cmd = APT_GET_CMD
        upgrade_command = "dist-upgrade"
    elif mode == "full": 
        # aptitude full-upgrade
        apt_cmd = APTITUDE_CMD
        upgrade_command = "full-upgrade"
    else:
        # aptitude safe-upgrade # mode=yes # default
        apt_cmd = APTITUDE_CMD
        upgrade_command = "safe-upgrade"

    if force:
        force_yes = '--force-yes'
    else:
        force_yes = ''

    apt_cmd_path = m.get_bin_path(apt_cmd, required=True)
    cmd = '%s %s -y %s %s %s %s' % (APT_ENVVARS, apt_cmd_path, DPKG_OPTIONS,
                                    force_yes, check_arg, upgrade_command)
    rc, out, err = m.run_command(cmd)
    if rc:
        m.fail_json(msg="'%s %s' failed: %s" % (apt_cmd, upgrade_command, err))
    if (apt_cmd == APT_GET_CMD and APT_GET_ZERO in out) or (apt_cmd == APTITUDE_CMD and APTITUDE_ZERO in out):
        m.exit_json(changed=False, msg=out)
    m.exit_json(changed=True, msg=out)

def main():
    module = AnsibleModule(
        argument_spec = dict(
            state = dict(default='installed', choices=['installed', 'latest', 'removed', 'absent', 'present']),
            update_cache = dict(default=False, aliases=['update-cache'], type='bool'),
            cache_valid_time = dict(type='int'),
            purge = dict(default=False, type='bool'),
            package = dict(default=None, aliases=['pkg', 'name']),
            default_release = dict(default=None, aliases=['default-release']),
            install_recommends = dict(default=True, aliases=['install-recommends'], type='bool'),
            force = dict(default=False, type='bool'),
            upgrade = dict(choices=['yes', 'safe', 'full', 'dist'])
        ),
        mutually_exclusive = [['package', 'upgrade']],
        required_one_of = [['package', 'upgrade', 'update_cache']],
        supports_check_mode = True
    )

    if not HAS_PYTHON_APT:
        module.fail_json(msg="Could not import python modules: apt, apt_pkg. Please install python-apt package.")

    global APTITUDE_CMD
    APTITUDE_CMD = module.get_bin_path("aptitude", False)
    global APT_GET_CMD
    APT_GET_CMD = module.get_bin_path("apt-get")

    p = module.params
    if not APTITUDE_CMD and p.get('upgrade', None) in [ 'full', 'safe', 'yes' ]:
        module.fail_json(msg="Could not find aptitude. Please ensure it is installed.")

    install_recommends = p['install_recommends']

    try:
        cache = apt.Cache()
        if p['default_release']:
            apt_pkg.config['APT::Default-Release'] = p['default_release']
            # reopen cache w/ modified config
            cache.open(progress=None)

        if p['update_cache']:
            # Default is: always update the cache
            cache_valid = False
            if p['cache_valid_time']:
                tdelta = datetime.timedelta(seconds=p['cache_valid_time'])
                try:
                    mtime = os.stat(APT_UPDATE_SUCCESS_STAMP_PATH).st_mtime
                except:
                    mtime = False
                if mtime is False:
                    # Looks like the update-success-stamp is not available
                    # Fallback: Checking the mtime of the lists
                    try:
                        mtime = os.stat(APT_LISTS_PATH).st_mtime
                    except:
                        mtime = False
                if mtime is False:
                    # No mtime could be read - looks like lists are not there
                    # We update the cache to be safe
                    cache_valid = False
                else:
                    mtimestamp = datetime.datetime.fromtimestamp(mtime)
                    if mtimestamp + tdelta >= datetime.datetime.now():
                        # dont update the cache
                        # the old cache is less than cache_valid_time seconds old - so still valid
                        cache_valid = True

            if cache_valid is not True:
                cache.update()
                cache.open(progress=None)
            if not p['package'] and not p['upgrade']:
                module.exit_json(changed=False)

        force_yes = p['force']

        if p['upgrade']:
            upgrade(module, p['upgrade'], force_yes)

        packages = p['package'].split(',')
        latest = p['state'] == 'latest'
        for package in packages:
            if package.count('=') > 1:
                module.fail_json(msg="invalid package spec: %s" % package)
            if latest and '=' in package:
                module.fail_json(msg='version number inconsistent with state=latest: %s' % package)

        if p['state'] == 'latest':
            install(module, packages, cache, upgrade=True,
                    default_release=p['default_release'],
                    install_recommends=install_recommends,
                    force=force_yes)
        elif p['state'] in [ 'installed', 'present' ]:
            install(module, packages, cache, default_release=p['default_release'],
                      install_recommends=install_recommends,force=force_yes)
        elif p['state'] in [ 'removed', 'absent' ]:
            remove(module, packages, cache, p['purge'])

    except apt.cache.LockFailedException:
        module.fail_json(msg="Failed to lock apt for exclusive operation")

# this is magic, see lib/ansible/module_common.py
#<<INCLUDE_ANSIBLE_MODULE_COMMON>>

main()
